MARCEL BETRISEY CREATIONS Sion Switzerland Phone: ++41 273238808 Mobile ++41 793801679 Email: see "Contact"
(Ball clock) This is a time display sculpture that reuses the ball engine principle proven by Anachrone and Florence: a bearing ball falls and
this is enough to sustain the pendulum's oscillation for a full hour. With Florence I had leardned that the engine was accurate,
reliable and above all that it gave me a freedom of implementation taht was mine to explore.
Here is the principle: every hour on the hour a ball falls into a labyrinth made of three pins and three holes. In its movement
downward it pushes the pendulum in the right direction. The amplitude gain is 5 millimetres, enough for one hour. An optical
sensor counts the pendulum's oscillations and advances the seconds hand of the clock. This principle leaves a lot of freedom as
to the choice of material, count on me to use it. The clock was made by recycling an old Gestetner printer (the so-called
Cyclostyle model, hence its name), an automatic bottling line handler and an old soap dispenser.
The ball elevator is a disk with one hole. It does one turn every hour, releases the ball at the top and retrieves it at the bottom,
once it has re-energised the pendulum. The ball falls into the hole, goes back up and waits for the next hour.
The clock started running at Christmas 99 and it is currently under test. It took three months to build and nine to fine tune. Its
accuracy is around a few seconds per month.
"The part that needed the most work and which I'm the most proud of is the heart (third picture). It had to implement 5 functions by
itself: release the ball every hour, push on the pendulum three times, retrieve the ball at the bottom, bring it back up and finally
position it at the top, waiting for the next hour. All this in a very limited space and as discretely as possible to make the essential
part, the steel cast chassis, most visible."